Far-reaching proposals to transform Britain into a carbon-neutral economy within 40 years won overwhelming backing from the Liberal Democrat rank and file yesterday.

Delegates at the party's annual conference in Brighton approved a series of measures, including plans to remove petrol-driven cars from the roads by 2040, invest billions in the railways and pour resources into renewable power to give Britain a network of non-carbon emitting electricity generators.

But an attempt by some delegates to lift the party's historic antipathy to new nuclear power stations was rejected, despite claims that the nuclear option was needed to prevent a greater reliance on gas and coal-fired plants. Chris Huhne, the party's environment spokesman, declared: "Do we want a world where the wind whips the tiles from our roofs, fells trees that have grown for generations, where it rains four inches in a day, the same as a normal month; rain that fills up the gutters and drains and sewers? We are tearing up nature by the roots."

He insisted he was not advocating a fall in living standards, adding: "My green vision for Britain is not about hair shirts but wholesome living. Far from being a bad life, the greening of Britain will be better, like the reformed smoker who can taste and smell again.

"In the countryside, a green Britain will mean clear streams, rich topsoil for growing vegetables and fruit, lusher grassland. In cities, it will mean Paris-style 'borrow-a-bike' schemes, public transport that works. Breathe deep in our parks because the air will be fresh and not reeking of diesel and petrol fumes. Homes will be warm by design, not by burning fossil fuels."

Mr Huhne said the party planned a sharp increase in vehicle excise duty on "gas-guzzling" cars, before an eventual ban on petrol-powered vehicles. "The EU Commission wants to set limits on car emissions but it should state clearly that no car can be sold in the EU if it still belches carbon by 2040," he added. "It can be electric. It can be fuelled by a hydrogen cell, but we have to get tough with car makers about emissions."

The party would raise vast sums by charging lorries to use Britain's roads, Mr Huhne said. This would be used to to double rail investment and possibly create a new high-speed line from north to south. The Lib Dems would also raise spending on flood defences, set guaranteed tariffs to encourage homeowners to generate their own power and set up an international "leapfrog fund" to help developing countries adopt low-carbon technology.

The new ideas did not escape criticism. John Allen, a delegate from Oxford West and Abingdon, said: "Climate change has always happened and it always will happen, stability is not possible. We might as well propose perpetual motion machines as party policy."

Chris Davies, an MEP, argued that the party should drop its opposition to building nuclear power plants. He said: "Britain's policy priorities should be energy saving, promotion of renewable sources of electricity and development of carbon capture and storage technology but, to bridge the gap and keep the lights on, we may have to consider replacing existing nuclear power stations on a like-for-like basis."